How many injections are needed after a rat bite? - briefly
Typically, a single tetanus booster is given, and if rabies exposure is possible, a four‑dose vaccine series is initiated. One dose of prophylactic antibiotics (e.g., amoxicillin‑clavulanate) is also recommended.
How many injections are needed after a rat bite? - in detail
When a person is bitten by a rat, the clinician must assess three separate prophylactic needs: rabies immunization, tetanus protection, and bacterial infection prevention. The exact count of injections depends on the individual’s immunization history and the risk assessment of the bite.
Rabies vaccine
- If the victim has never received rabies pre‑exposure series, the standard post‑exposure schedule consists of four intramuscular doses administered on days 0, 3, 7, and 14. In some protocols a fifth dose on day 28 is added for high‑risk exposures.
- For individuals who completed a full pre‑exposure series (three doses), only two booster doses are required, given on days 0 and 3.
- When the patient has previously completed a full post‑exposure regimen within the past three years, a single booster dose on day 0 may suffice.
Rabies immune globulin (RIG)
- For patients without prior rabies vaccination, a single dose of human RIG is infiltrated around the wound at the time of the first vaccine injection. This adds one additional injection to the regimen.
Tetanus toxoid
- If the last tetanus booster was administered more than five years ago, a single dose of tetanus‑containing vaccine (Td or Tdap) should be given concurrently with the first rabies shot. If the patient’s immunization is up‑to‑date, no extra injection is needed.
Antibiotic prophylaxis
- A standard oral regimen of amoxicillin‑clavulanate for five to seven days is recommended for most rat bites. This treatment does not involve an injection, but it is part of the overall management plan.
Summary of possible injections
- No prior rabies vaccination: 4–5 rabies doses + 1 RIG + 1 tetanus booster = 6–7 injections.
- Prior rabies pre‑exposure series: 2 rabies boosters + 1 tetanus booster (if needed) = 2–3 injections.
- Prior full post‑exposure series within three years: 1 rabies booster + 1 tetanus booster (if needed) = 1–2 injections.
The exact number is determined by the patient’s vaccination record and the time elapsed since the last tetanus booster. Prompt wound cleaning, thorough debridement, and appropriate antibiotic coverage are essential components of care, regardless of the injection count.